Mohamed ElBaradei, head of the IAEA, says the world must engage with Iran
The head of the International Atomic Energy Agency says he believes Iran is mastering nuclear technology and it wants the option of a nuclear weapon.
Mohammed ElBaradei told the BBC that countries with nuclear weapons were treated differently to those without.
He said North Korea, with a bomb, was invited to the conference table, while Saddam Hussein's Iraq, without one, was - as he put it - pulverised.
But an Iranian official said his country did not want a nuclear bomb.
He was responding to Mr ElBaradei's comments, in which he called for engagement with Iran to remove the incentive for making a bomb.
"It is my gut feeling that Iran would like to have the technology to enable it to have nuclear weapons, if it decides to do so," Mr ElBaradei, director general of the IAEA, told the BBC's Middle East Editor Jeremy Bowen.
"They want to send a message to their neighbours, to the rest of the world, don't mess with us.
"But the ultimate aim of Iran, as I understand it, is they want to be recognised as a major power in the Middle East.
"This is to them the road to get that recognition, to get that power and prestige. It is also an insurance policy against what they have heard in the past about regime change."
But Ali Asghar Soltanieh, Iran's ambassador to the IAEA said Mr ElBaradei was "absolutely wrong".
"We don't have any intention of having nuclear weapons at all," he told reporters.
"But we are going to have nuclear technology for peaceful purposes. We will continue fuel cycle activities without any interruption because Iran has a legitimate need."
In the wider world, Mr ElBaradei said the biggest threat was the prospect of a nuclear weapon falling into the hands of an extremist group.
He said the principle of nuclear deterrent would not apply to such groups.
The only safe future, he said, was widespread nuclear disarmament led by the existing nuclear powers which between them have 27,000 warheads.
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